Effect of Sulfur Incorporation on Coercivity in CoFe Nanowires

In this study we report for the first time the effect of sulfur incorporation on coercivity in CoFe nanowires. The CoFe alloys were deposited from a sulfate bath with varying concentrations of thiourea in polycarbonate membranes. The physical incorporation of sulfate anions from the electrolyte was also taken into account as a source of sulfur which was not considered earlier. The deposition was done potentiostatically to control the composition of the CoFe nanowires. A low coercivity (soft nanowire) in the range of 120-130 oersteds was obtained for samples containing low S at%. Also the amount of sulfur seemed to have an effect on the microstructure of the deposits. A low thiourea concentration was determined to be ideal to achieve low coercivities. Composition and surface morphology was studied using EDAX and SEM respectively. Coercivity was studied using an Alternating Gradient Magnetometer (AGM) with fields applied upto 1Tesla.